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		<title>three.js webgpu - shadowmap + opacity</title>
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			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgpu - shadowmap + opacity
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		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.webgpu.js",
					"three/tsl": "../build/three.webgpu.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';
			import { Fn, vec4 } from 'three/tsl';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';

			let camera, scene, renderer;

			init();

			async function init() {

				const container = document.createElement( 'div' );
				document.body.appendChild( container );

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.1, 40 );
				camera.position.set( - 4, 2, 6 );

				renderer = new THREE.WebGPURenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( render );
				renderer.toneMapping = THREE.AgXToneMapping;
				renderer.toneMappingExposure = 1.5;
				container.appendChild( renderer.domElement );

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x9e9eff );

				// light + shadow

				const hemi = new THREE.AmbientLight( 0xffffff, .5 );
				scene.add( hemi );

				const dirLight = new THREE.DirectionalLight( 0x6666ff, 10 );
				dirLight.position.set( 3, 5, 17 );
				dirLight.castShadow = true;
				dirLight.shadow.camera.near = 0.1;
				dirLight.shadow.camera.far = 50;
				dirLight.shadow.camera.right = 5;
				dirLight.shadow.camera.left = - 5;
				dirLight.shadow.camera.top	= 5;
				dirLight.shadow.camera.bottom = - 5;
				dirLight.shadow.mapSize.width = 2048;
				dirLight.shadow.mapSize.height = 2048;
				dirLight.shadow.radius = 4;
				dirLight.shadow.bias = - 0.0005;

				dirLight.shadow.autoUpdate = false;
				dirLight.shadow.needsUpdate = true;

				scene.add( dirLight );

				//

				const loader = new GLTFLoader();
				const gltf = await loader.loadAsync( 'models/gltf/DragonAttenuation.glb' );
				gltf.scene.position.set( 0, 0, - .5 );

				const floor = gltf.scene.children[ 0 ];
				floor.scale.x += 4;
				floor.scale.y += 4;

				const dragon = gltf.scene.children[ 1 ];
				dragon.position.set( - 1.5, - 0.8, 1 );

				const dragon2 = dragon.clone();
				dragon2.material = dragon.material.clone();
				dragon2.material.attenuationColor = new THREE.Color( 0xff0000 );
				dragon2.position.x += 4;
				gltf.scene.add( dragon2 );

				// shadow node

				const customShadow = Fn( ( [ color, opacity = .8 ] ) => {

					return vec4( color, opacity );

				} );

				// apply shadow

				floor.receiveShadow = true;

				dragon.castShadow = dragon2.castShadow = true;
				dragon.receiveShadow = dragon2.receiveShadow = true;

				dragon.material.shadowNode = customShadow( dragon.material.attenuationColor );
				dragon2.material.shadowNode = customShadow( dragon2.material.attenuationColor );

				//

				scene.add( gltf.scene );

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.minDistance = 0.1;
				controls.maxDistance = 10;
				controls.target.set( 0, 0, 0 );
				controls.update();

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			//

			function render() {

				renderer.render( scene, camera );

			}

		</script>

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